Hydraulic ejection equipment for missiles



RQWOSAK HYDRAULIC EJECTION EQUIPMENT FOR MISSILES June 10, 1958 3 sneaks-sheet 1 Filed Sept. 3, 1952 INVENTOR. Rosa/FT WOSAK 3 Sheets-Sheet 2 INVENTOR. Roam? WosAK ATToR/vL-m' June 10, 1958 R. wosAK HYDRAULIC EJECTION EQUIPMENT FOR MISSILES Filed Sept 3, 1952 June 10, 1958 R. WOSAK v 2,837,971

HYDRAULIC EJECTION EQUIPMENT FOR' MISSILES Filed Sept. 3, 1952 3 Sheets-Sheet 3 PRESSURE PRESSURE VENT INVENTOR. ROBERT WosAK Arron/wk;

United States Patent 2,837,971 7 HYDRAULKI EJECTION EQUIPMENT FOR MISSILES Robert Wosak, Quaker Hill, Conn., assignor to General Dynamics Corporation, New York, N. Y., a corporation of Delaware Application September 3, H52, Serial No. 307,637 9 Claims. (Cl. 89-5) This invention relates to the hydraulic expulsion of torpedoes, mines, and similarly shaped missiles from submerged tubes such as used on submersible ships and similar ships or installations of defense or offense.

.For convenience of description the invention may be said to relate to the expulsion of torpedoes from the torpedo tubes of submarines as it is in this type of installation that the invention is particularly well suited for use. However, it will be understood by those skilled in the art that the invention lends itself to use in other installations designed to expel missiles from a tube under water. a

The expulsion of torpedoes from the torpedo tubes'of submarines is of course not new in a broad sense. Heretofore it has been a common practice to eject the torpedo from the torpedo tube by compressed air introduced into the tube behind the torpedo. (known as an unbalanced system) the compressed air has to be suificient to overcome the hydraulic pressure exerted on the open discharge end of the tube, in addition to that required to produce the necessary force to expel the torpedo from the tube. With such a system it is manifest that the air pressure or force required to expel the torpedo will vary with the submergence depth of the expulsion tube beneath the surface of the-sea. Furthermore, in a system in which compressed air is injected into the tube there is likelihood of air being discharged from the tube which rises to the surfaceto produce a telltale of the location of the submarine.

This prior system of ejecting torpedoes from a submerged tube in which there is no provision for balancing the hydraulic pressure or head of water on the tail and head ends of the torpedo inthe tube at the time it is.

expelled is subject to an inherent drawback. Despite many refinements made from time to time in this so-called unbalanced system, it still is subject to the requirement that in order to expel the torpedo from the tube, the air pressure has to be regulated to overbalance the submergence pressure which in turn is dependent upon the depth of the ship beneath the surface of the sea.

In contrast to the above mentioned unbalanced system it has been proposed to utilize a balanced system that In this type of system 2. i i v and this force is substantially the same regardlessof variation of depth of the sea.

Although the theoretical advantages of utilizing a bal anced system for the ejection ofa torpedo from asubmerged tube have been recognized, the provision of means for accomplishing the desired ends in a practical and successful manner has presented problems which are solved and difiiculties which are overcome by utilizing the present invention. I

According to this invention a system is provided which comprises a water filled cylinder communicating at one end with the sea and communicating at its other end, through ports in its walls and a suitable passageway or conduit with the aft end of a-missile ejector tube whose fore or discharge end communicates with the sea. piston is mounted for reciprocatable movement in the water cylinder and the piston is connected to a suitable driving mechanism for moving the piston forward from its retracted position to force water ahead of the piston through the ports in the forward end of the Water cylin der through the conduit connecting those ports with the aft end of the missile ejector tube thereby to charge the water into the ejector tube behind a missile in the tube and in sufficient amount and with sufiicient force to expel the missile from the tube with the desired force and velocity. j A significant feature of the invention is the provision of the porting of the water cylinder and a piston mounted for reciprocation in this cylinder arranged in, such manner that when a missile is in place in the ejector tube with the discharge endof the ejector tube open and in communication with the sea and the breech door at the aft end of the tube is closed and the piston is moved forward from its retractedposition, water in the water cylin der in advance of piston is moved forward and forced through the ports at the forward end ofthe water cylinder, through the conduit which connects these ports with the aft'end of the ejector tube, and then into the ejector tube behind the missile, thus ejecting the missile, while water displaced from the water cylinder moving in advance of the piston is replaced behind the piston by water drawn in from the sea at the aft end of the water cylinder. length, is less than the length of the ports and thearrangement is such that the face of the piston reaches the rear end of the ports shortly beforethe piston reaches the end of its forward travel in the water cylinder and the back of the piston reaches the'rearend of the ports before would overcome the inherent drawbacks of the unbalanced system. The proposal has been made of providing a system in which not only the'open discharge end of the torpedo tube is in communication with the ambient sea but the rear end of the torpedo tube is also in communication with the ambient sea after the torpedo is placed in the tube and prior to and at the time of expulsion of the torpedo fromthe torpedo tube. 'In the balanced system, the hydrostatic head or pressure is the same, or substantially so, behind the torpedo as it is at the open discharge end of the tube, regardless of the depth of the submarine beneath the surface of the sea. Inasmuch as the pressure is thus balanced in advance of and behind the torpedo in the torpedo tube regardless of depth, the force required to expel the. torpedo from the tube is only that required toproperly expel the torpedo the piston reaches the end of its forward travel. Hence, during the time the piston in its forward stroke is traversing the ports, the exposed open area of the ports in advance of the piston face is progressively decreased as the piston is reaching the 'end of its forward stroke and meanwhile the. exposed open area of the ports behind the back of the piston is progressively increased; Consee quently, the water ahead of the piston will be forced through a diminishing flow area or section, thusincreasing the pressure in the portion of the water cylinder ahead of the piston and thus increasing the force opposing the forces moving the piston and the inertia ofthemoving masses, thus slowing theqvelocity of the piston and:

while at the same time applying this additional force'be hind the missile to impart a final pushing force 7 asjthe missile is being expelled from the tube on its way toward P a tented June 10,

of the submarine beneath the surface.

The thickness of the piston, that isits skirt However, some types of missiles, such as mines and the like do not require their own propelling mechanisms, it being necessaryto expel the mines with only sufficient force to clear the ship structure.

, Dissipation of the energy built up by the mass of moving water which flows behind the piston in its forward stroke in a manner as provided by the invention is partic'ularly advantageous because unless some provision is made to direct the stored up energy of this moving mass of water into the ejector tube and thence to the sea, all of this energy stored in the moving mass of water following the piston will have to be dissipated within the structure because when the piston is stopped at the end of its forward stroke, an opposing force will be necessary. In the absence of a porting arrangement such as provided by the invention, this opposing force is built up by the hydraulic pressure ahead of the piston which will increase as the piston'reaches the end of its forward stroke. Also, in the absence of providing such an escape port back of the piston at the end of its stroke for the energy stored in-the moving column of water which follows the piston, the moving mass of water ahead of the piston and now moving forward in the expulsion tube will, upon stopping the piston, result in a suction or force tending to pull the piston further forward since the column of water ahead of the piston is moving in a direction away from the now stopped piston with the result that an increased strain is th'rovm upon the supporting structure. In accordance with the invention these unwanted strains upon the structure are eliminated or at least minimized to fullest extent by providing a porting arrangement back of the piston effective to provide an escape for the energy built up in the moving mass of water following the piston in its forward stroke and this may be arranged in a way which utilizes the built up energy to perform useful and effective work in that it is directed into the ejector tube behind the missile being expelled.

Although thenovel features which are characteristic of the invention are pointed out in the annexed claims, the invention itself and the manner in which it may be garri'ed out may be better understood by reference to the following description taken in connection with the accompanying drawings forming a part hereof in which Fig. 1 is, primarily, a diagrammatic and schematic longitudinal vertical section taken'along the line 1--1 of Fig. 2 and showing an installation illustrating the 1 general arrangement of an embodiment of the invention inwhich the upper torpedo ejector tube is being loaded and the lower torpedo ejector tube is loaded and ready for theop'erations to prepare for firing.

Fig. 2 is a transverse section taken along the line 22 of Fig. l and showing a battery arrangement of four ejector tubes adapted to be served by a single water cylinder for torpedo ejection.

Fig. 2A is a purely diagrammatic view, similar to Fig. 2 but showing a different battery arrangement wherein six ejector tubes are provided of which three are served by one water cylinder and the remaining three by another water cylinder.

Fig. 3 is a view of a portion of Fig. l on a slightly larger scale but showing the positions of the various units as they near the end of a firing cycle of the lower torpedo ejector tube.

Fig. 4 is a fragmentary view of the forward end of a water cylinder and showing the piston during a forward stroke with its front face about to pass the water ejection ports and a graphical representation of water pressure reaction on the front face of the piston during its passage over the ports.

Fig. 5 is a fragmentary view of the forward end of a water cylinder illustrating the piston at the end of its V 4' forward stroke as brought to a full stop by an elastomer bumper stop in the cylinder forward end wall.

Fig. 6 is a longitudinal vertical section of the firing valve shown in Fig. l and illustrating the locations of the valve parts in their non-firing or closed position as during the return of the air cylinder piston to its retracted position after a firing operation.

Fig. 7 is a view similar to Fig. 6 but showing the valve parts in their firing or open position whereby the air piston is rapidly propelled forward to effect the ejection of a torpedo from its ejector tube.

Referring now to the drawings, in which like reference characters denote like parts in the several views, the general arrangement of an installation embodying the invention, as illustrated in Figs. 1, and 2, comprises missile ejecting tubes 10a, 10b, 10c and 10d (herein referred to as torpedo ejection tubes) arranged as a battery; a water cylinder 11 having a water piston 12 mounted therein for reciprocation; an air cylinder 13 having an air piston 14 connected to water piston 12 by a piston rod 15, said air piston being mounted in theair cylinder for reciprocation; a firing valve 16 connected to a source of compressed air or other gaseous fluid, such as compressed air in i1npulse tank 17, for actuating the firing valve 16 which in turn permits the compressed air to flow from impulse tank 17 through valve 1.6 to operate air piston 14 and consequently water piston 12 in cylinder 11. The aft end of the water cylinder is connected by a water passageway 18 to the sea, indicated by reference character 20, surrounding the hull wall 21 of the submarine S. The cylindrical wall 22 of the water cylinder 11 at its fore end is provided with ports, preferably a plurality of elongated port openings 23 tapered and converging in forward direction and circumferentially spaced around the cylindrical wall. These ports connect the interior of water cylinderll with the interior of a plenum cham: ber 24 which provides a conduit or passageway 25 from the water cylinder to each'of the ejector tubes 10a, 10b, 10c, Md. The cylindrical wall 26 of each of the ejection tubes'is provided with a plurality of ports 30 located at the aft end portion of the tube and circumferentially spaced around its cylindrical wall 26. The set of ports 30 for each tube is provided with an openable and closeable valve, which, as shown, is a slidable sleeve valve 31. Thus the plenum chamber 24 provides a passageway 25 through which water may pass between the interior of each ejector tube 10a, 10b, 10c, 10d, through the ejector tube water ports 30 of each of the tubes and through the water cylinder ports 23.

The passageway 18 through which the aft end of water cylinder 11 communicates with the sea is provided by a housing 32, having an opening 33 for that purpose. The rear wall 34 of the housing is provided with a packing gland 35 through which piston rod 15 may reciprocate and also has an inwardly extending cup shaped dash pct 36 having a relatively small escape vent '37. The dash pot is located inside the housing 32 and is adapted to receive a dash pot piston 38 which is fixed to piston rod 15. The location of dash pot piston 38 on piston rod 15 is such that when the pistons 12 and 14 are returned from the forward position to retracted position as indicated in Fig. 1, the rearward movement of the piston assembly is effectively cushioned or dampered to avoid shock at the end of the return stroke.

The plenum chamber 24, as shown, comprises a forward wall 40 which may be exposed toflthe sea, a rear wall .41 spaced from wall 40 and enclosed at its periphery by a side wall 42 which in this instance is shown as the hull wall 21 of the submarine S at its aft end. It will be observed that the fore end of water cylinder 11 extends through the walls 40 and 41 and the ejection tubes 10a, 10b, 10c, 10d also extend through these walls so that their forward ends extend into the sea and their aft ends extend into the interior of the submarine where the operatingmechanisms are located so as to be acces} sible to the crew men. Thus the plenum chamber housing surrounds the ejection tubes and water cylinder as' a closure over the water ports 30 of the ejection tubes and the water ports 23 of the water cylinder. The fore ends of the ejection tubes 10a, 10b, 10c, 10d may be surrounded by the usual hinged walls and superstruccumferentially spaced water ports 30 are located. Slida able within the ported sleeve 45 is the sleeve valve 31. Secured to sleeve valve 31 and depending therefrom is an arm 47 fixed to a reciprocatable rod 48 .slidable in packing glands 49 and 50, which, as shown, are mounted on a bored flange 51 of the ejector tube and the wall housing 40. The fore end of slide rod 48 is pivotally connected to a link 52 in turn pivotally connected to an arm 53 secured to hinged muzzle door 54. An hydraulically operated piston connected to rod 48 and reciprocatable in hydraulic cylinder 590 (or 59b on tube 10b which is of like construction) serves as means to reciprocate rod 48, it being noted that on the forward stroke of arm 48, sleeve valve 31 is moved forward to open ports 30 and arm 53 operates to swing muzzle door 54 on its hinge and open it, as illustrated in Fig. 3. Movement of the rod 48 rearwardly to retracted position, as illustrated in Fig. 1. moves the sleeve valve 31 rearward wardly to close ports 30 and to close muzzle door 54.

Each of the hydraulic cylinders of each ejectortube in the battery is connected by suitable pipes and valves with a source of fluid, such as oil, under pressure. As illustrated in Fig. 1 line 60:: at the forward end of the cylinder 59a connects with valve 61a and line 62a at the rear end of cylinder 59a connects with this valve which is connected to line 63a, in turn connected to line 64 (labeled Return). Valve 61:: also connects with line 64a in turn connected to line 65- (labeled Hyd. Pressure) which is connected to a source of fluid under pressure. The return lines are provided with check valves 66a and 66b. It will be understood that all the hydraulic cylinders in the battery for operating the sleeve valves are connected with the high pressure lines and return lines in the same fashion and each may be operated independently. The hydraulic system for hydraulic cylinder 59b is the same as that for hydraulic cylinder 59a and corresponding parts are indicated by the same reference numerals with the sub-letter b. It will therefore suffice to describe the operation of cylinder 59b, having particular reference to Figs. 1 and 3. When valve 61b is rotated as shown in Fig. 1 so that line 62b communicates with line 63b and line 60b communicates with line 64b, hydraulic pressure is exerted through line 65 so that the hydraulic piston 67b in cylinder 59b is driven to rearward position, as shown in Fig. 1; fluid behind the piston returning to storage (not shown) through return line 64. When valve 61b is rotated 90 so that lines 60b and 63b communicate and the line 62b and 64b communicate, hydraulic pressure is exerted through line 65 so that the piston 67b in the hydraulic cylinder 59b is driven forward; the fluid in advance of the piston. returning to storage through return line 64.

The aft end of each ejector tube 10 (a, b, c, d is pro vided with an openable and closeable breech door which may be of known construction. As shown, a typical breech door 7011 on tube 10a is mounted on a hinge 71 and the tube provided with a rotatable locking ring 72, which may be used to lock the breech door when closed.

The battery of ejector tubes is provided with a system of pipes and valves for filling the tubes with water and for emptying them at certain times during any operating cycle. This arrangement is illustrated in Fig. 1

wherein it will be seen that a vent pipe 73a connected to ejection tube a and it has an openable and closeable vent valve 74a. Vent pipe 73b is connected to ejection tube 10b and it has a valve 74b. The other ejection tubes (not visible in Fig. 1) have like vent pipes and valves. A water pipe 75a connects with tube 10a to branch pipes 766 and 77a. Pipe 76a connects with a pipe 78 which connects with a water reserve tank 81. Pipe 77a connects with a pipe 79 which connects with the sea through the passageway 18 of housing 32. A valve 804 is provided so that upon rotation it can be set to provide communication between pipe 75a and 76a or between pipes 75a and 77a. The corresponding connections for ejector tube 10b are like the connections for ejector tube 10a. The corresponding parts are designated 75b, 76b, 77b. Pipe 76b is connected to pipe 78 to water reserve tank 81 and pipe 77b is connected to pipe 79 to passageway 18 to the sea. The other ejector tubes of the battery are provided with similar connections to pipes 78 and 79.

Compressed air cylinder 13 is provided with a systern for actuating the air piston 14 by means of a gaseous fluid under pressure, such as compressed air. Mounted on the aft end of cylinder 13 is a firing valve 16 which is operative to direct compressed air into cylinder 13 behind piston 14 to drive the piston 14 in a forward stroke in cylinder 13 and consequently to drive water piston 12 in a forward stroke in cylinder 11. Also means are provided to drive the air piston 14 to return it to retracted position after a forward stroke and consequently to return water piston 12 to retracted position, as illustrated in Fig. 1. 1

This arrangement comprises a compressed air supply pipe 85 which is connected to a source of compressed air (not shown). Connected to compressed air supply pipe 85 is a pipe 86 having a valve 87 to which is connected a pipe 38, in turn connected to fore end of air cylinder 13. A vent pipe 89 is also connected to valve 87. Valve 87 can be rotated to provide communication between pipes 86 and 88 or between pipes 88 and 89. Connected to air supply pipe 85 is a pipe 90 whichconnects with compressed air tank 17 (labeled Impulse Flask). Pipe 90 has a shut-off valve 91 to prevent flow of air back into supply pipe 85 after tank 17 hasbeen filled and an adjustable relief valve 92 so that theair pressure in impulse flask 17 may be adjusted to the called a trigger valve) connects with pipe 96' which is connected to therear end of firing valve 16. Connected to this trigger valve' 95 is a vent pipe '97 which may, if

desired, be connected to a mufiier (not shown). It will be seen that by rotating valve 95, pipe 94 may be put in communication with pipe 96 to supply air pressure in pipe 96 to the firing valve 16;-or, pipe 96 may be put in communication with vent pipe 97 to permit air pressure to escape from pipe 96 to atmosphere through the vent 97.

The firing valve itself, as shown in detail in Figs. 6 and 7, comprises a valve housing 100 of generally cylindrical shape secured to the open rear end of air cylinder 13 by means of a retaining ring 101 threaded onto the cylindrical wall of the air cylinder. Mounted for reciprm cation in the housing bore 102 is a slide valve 1080f generally cylindrical shape having an internal bore 103 open at its rear end and closed at its forward end by a nose 104 having a bevelled annular seating portion 105 which, when the valve is closed, seats upon a complementary bevelled annular seat 106 at the fore end of the valve housing. A compression spring 107 urges the valve 108 toward closed position. The valve housing 100 has an annular groove 109 and an annular groove'110in assms'rr groove 110,,through the housing wall to the interior of theaircylind'er 13. The slide valve 108 has a groove 1'13'inits exterior cylindrical surface which is wide enough to'span both grooves 109 and 110 when the valve is in closed position as shown in Fig. 6. in this closed position communication between the interior of cylinder 13 is provided to the atmosphere, through conduit 112, grooves 109, 1l0, 113 and vent 111. When the valve is open the vent is closed since the cylindrical portion 114 of the valve closes off vent conduit 112, as shown in Fig. 7. Pipe 93 (see Figs. 1, 6 and 7) connects with a chamber 115 in the valve housing, through which the valve nose 104 may travel. Pipe 96 connects through the end closure 116 of the valve housing into the central bore-102 of the valve housing.

From the foregoing description it will be observed that the firing valve 16 is a so-called unbalanced valve. When pressure from supply line 85 is exerted in line 93 and line 96, as when valve 95 is in the position shown in Fig. 1 so that vent 97 is closed, equal air pressure is exerted on both ends of the valve and the spring 1&7 maintainsthe valve in closedposition as shown in Fig. 6. If trigger valve 95 is rotated so as to close line 94 and open line 96 to the vent 97, the air pressure in the valve bore 102 .is suddenly released while the pressure in line 93 exerts its force on shoulder 104 of nose 104- and moves the-valve rearwardly against the force of spring 107, thus opening the valve and permitting compressed air to pass through pipe 93 through chamber 115, through the central opening 117 in the valve housing into the cylinder 13. Ordinarilythe amount of air pressure carried in supply line 85 from air compressors (not shown) will be of the order of 2500 to 3000 pounds per square inch. The relief valve 92 may be set so that the pressure impulse flask may carry a pressure of the order of 2000 to 2500 per square inch at the time of firing a torpedo.

An important and significant feature of the invention resides in the porting and piston arrangement of the water cylinder 11. As shown perhaps best in Figs. 3, 4 and 5, the cylindrical wall 22 of the water cylinder at its fore end is provided with a porting arrangement comprising a plurality of ports 23, circumferentially spaced around the periphery of the cylinder. Preferably the ports 23 are elongate and at their forward ends are tapered so as to provide a V shaped portion 120, the apex of which terminates just short of the place where the face 121 of 'the piston 12 reaches the end of its forward stroke, 'as illustrated in Fig. 5. The skirt portion 122 of the piston 12 is of a length less than the length of the elongate ports 23 and the back 123 of the piston is, as shown, spheroidal in shape. This shape aids in directing the Water following piston 12, as later described, through ports 23 as the piston 12 traverses the ports in its forward stroke. If desired, the back of the piston may be more streamlined, although the spheroidal form of back has been found in actual use to be very satisfactory. As mentioned before, a dash pot piston 33 is secured to the piston rod, this piston cooperating with dash pot cup 36 on the return stroke of water piston 12 to retracted position (see Fig. l). Extending outwardly from face 121 of piston 12 is a bumper member or boss 124 (see Figs. 4, and which engages a resilient or elastomer bumper member or stop 125 which is mounted and retained in 'a'bore 126 of a hollow boss 127 fixed to and extendinginwardly from the end wall 123 of the water cylinder. It will be observed that the open end of the bore 126 is flared at 129. Fig. 3 illustrates the position of the elastomer bumper step 125 prior to being engaged by the bumper 124 and Fig. 5 illustrates the position of the bumper 124 and elastomer stop 125 when the piston has come to rest at the end of its forward stroke. The elastomer stop prevents metal to metal contact and muiiles noise that might otherwise be caused by impact of one metal part against another metal part.

.It may be noted here that the arrangement of the porting 0f the water cylinder and of the water piston having a skirt length less than the length of the water ports over which the piston traverses is such that when the face 121' of piston 12 in its forward stroke reaches the rear'end of ports 23, the efiective area of the port opening is the entire areas of the ports, as illustrated in Fig. 4. As the piston 12 continues in its forward stroke, the effective open area of the ports is progressively diminished. \Vater which was in the water cylinder in advance of the piston as the piston moves forward from its retracted position forces this water out of the water cylinder into plenum chamber 24. If, for example, a torpedo Tb is to be ejected from ejector tube 10b (as illustrated in Fig. 3), breech door 70b is closed, torpedo has been inserted in water cylinder 10b, valve 31 and muzzle door 54 for this tube have been opened, hence the water forced into plenum chamber 24 passes through ports 30 into ejector tube 10b to exert its force on the tail end of the torpedo to move it forward in the tube'. Since the open effective area of the ports in advance of the piston face 121 becomes smaller and smaller after piston face 121 passes the rear ends of the ports 23 the force tending to stop the forward movement of the piston and opposing this forward movement builds up in the water cylinder in the space between end wall 128 of the Water cylinder and the piston face. This opposing force is represented graphically in the lower portion of Fig. 4 wherein it will be noted that the curve 130 represents opposing force or back pressure plotted as ordinates and distance of travel over the ports as abscissae. It will be noted that the ports are so designed and shaped that the opposing force rises rapidly soon after the piston face passes the rear ends of the ports 23, then the opposing force remains substantially constant for a short distance of travel and finally as the face of the piston traverses the V-shaped portion 120 of the ports, the back pressure or opposing force falls to zero, bearing in mind that the air pressure from impulse flask 17 which is utilized to drive air piston 14 forward will have largely been expended by the time the water piston 12 reaches the end of its forward stroke and bearing in mind that after the back 123 of piston 12 passes the rear end of ports 23, the effective area of escape for the energy built up in the mass of water following behind the piston (which has been drawn into the cylinder from the sea through passageway 18) is progressively increasing. The relative open areas of the ports in advance of and behind the piston slightly before the piston reaches the end of its forward stroke is illustrated in Fig. 3. And it is significant to note that the energy built up in the moving mass of water moving behind the piston escapes through the open area of the ports behind the piston, carrying the water through these ports into the plenum chamber 24, through the water ports 30 of ejector tube 10b (see Fig. 3) where it exerts a final push against the tail end of the torpedo Tb' just as it is being ejected from the ejector tube and, of course, this energy is then dissipated through the tube to the ambient sea.

It is further significant to note that inasmuch as the hydraulic pressure at passageway 18 is substantially the same as the hydraulic pressure at the muzzle end of the ejector tube, the system is a truly balanced system. Accordingly the same force may be used to eject a torpedo irrespective of the sub'mergence depth of the submarine.

Cycle of operation For the purpose of describing a complete cycle of operation of an installation embodying the invention, in a submerged submarine such as illustrated in the drawings, it may be assumed that torpedo Ta is being inserted into ejector tube, 10a, as shown in Fig. 1, it being noted that breech door 70a is open, ports 30 for this tube and muzzle door 54 for this tube being in closed position. Valve a is adjusted so that pipe 75a communicates with pipe 76a to tank 81. Vent valve 74a is open. After torpedo Ta is loaded, breech door 70a is closed and locked. Torpedo Ta will then be in the position asis indicated for torpedo Tb in tube 10b; that is, breech door, muzzle door and ejector tube water ports are closed. Proceeding now with the cycle, with reference to tube 10b, the next step is to fill the loaded ejector tube with water and under the same pressure as the ambient sea. This is done by adjusting valve 80b, if for tube 10b, (or 80a, if for tube 10a). Confining the further description now to tube b, valve 80b is rotated to provide communication be- 7 85. Valve 16 is in closed position as shown in Fig. 6

because trigger valve 95 is adjusted so that pipe 94 communicates with pipe 96 leading into the bore 102 of valve 16. Valve 87 is rotated to shut off air pressure from line 85 and to provide communication between pipes 88 and 89 so that pipe 88 is vented to atmosphere. relief valve 92 has been adjusted to provide the desired pressure in impulse flask 17. The hydraulic pressure in tube 10b having been equalized with the ambient sea pressure, valve 61b is rotated to cause oil under pressure to pass from high pressure line 65 into hydraulic cylinder 59b to drive piston 67b and hence rod 48 forward. This opens ejector tube water ports 30 for tube 10b and also muzzle door 54 for this tube, these being shown in open position in Fig. 3. Conditions are now set to fire torpedo Tb from tube 10b.

To fire the torpedo, that is to expel or eject it from the ejector tube, triggervalve 95 is rotated so that pipe 96 communicates with vent pipe 97. This suddenly re leases the pressure from bore 102 which with spring 107 has been holding valve closed (as illustrated in Fig. 6)

against the line pressure in pipe 93. When the pressure is released from behind slide valve 108 to atmosphere through vent 97, the pressure from impulse flask, which is of the order of 2000 to 2500 pounds per square inch forces valve 108' to open against the force of spring 107 and permits the compressed air from the impulse flask 17 to pass through port 117 in the valve housing, into air cylinder 13 behind piston 14.

The air pressure from flask 17 drives air piston 14 forward and consequently drives water piston 12 forward. This drives the water in water cylinder 11 in advance of the piston 12 through ports 23 into plenum chamber 24, through ports 30 of tube 10b which drives torpedo Tb forward and, as described above, the water which is drawn in behind piston 12 in its forward stroke from the sea through passageway 18, follows behind the piston. The energy built up in this mass of water'moving behind the piston is ultimately dissipated through the ports 23 behind the piston 12-as the piston is being stopped and comes to rest at the end of its forward stroke. The torpedo Tb, having been ejected from the tube, is then propelled through the water by its own propelling mechanism in a manner known to those skilled in the art.

To make ready to fire another torpedo from tube 10b, air piston 14 and hence water piston 12 are returned to retracted position. This is done by having .valve 95 set to provide communication between pipes 94 and 96. This moves slide valve 108 of the firing valve to closed position (as shown in Fig. 6). Hence, the space back of piston 14 is vented through conduit 112, groove 110, groove 109 and vent pipe 111. Valve 87 is set to provide communication between pipes 86' and 88 so that air pressure from supply line 85 drives piston 14 rearwardly to its retracted position (as shown in Fig. 1).- This, of course, moves piston 12 from its forward to its retracted position and draws water from the sea, through open muzzle end of tube 10b, through its water ports 30,

The

through water cylinder ports 23; This fills water cylinder 11.

Next the muzzle door 54 and the water port valves 31 for tube 10b are closed by actuation of hydraulic cylinder 59b in a manner described hereinbefore. Valve b is set to put pipe 75b in communication with pipe 76b (as shown in Fig. 1). Such pressure as then exists in tube 10b is relieved and water in the tube flows into water tank 81. In the meantime vent valve 74b is opened to permit air to flow into tube 10b until all water in the tube is drained into tank 81. One of the reasons for draining this water into tank 81 is to replace the weight. which left the submarine by reason of discharging the torpedo from it.

After the tube 10b is freed of water its breech door 70b is opened and another torpedo is inserted into this tube. The breech door 70b is then closed. Now valve 80b .is set to provide communication between pipe 77b and 75b. Then water is driven by the hydrostatic pressure of the sea from passageway 18, through pipe 79, pipes 77b and 75b into tube 10b. As soon as water appears at vent 74b, it is known that tube 10b is full of water at the pressure of the ambient sea. Vent 74b is closed and valve 80b is closed. Tube 10b is now ready to be fired again thus completing a full cycle of operation.

Although a full operating cycle has been described only in connection with ejector tube 10b, it will be understood from the foregoing description that the other ejector tubes may be operated and torpedoes fired from them by following the cycle in similar fashion as that described above for tube 10b. Also, if desired, all the ejector tubes of the battery'may be made ready for firing and the torpedoes ejected therefrom in rapid succession by successive cycles of the water piston driving mechanism, Thus a choice of methods of firing is provided. The invention lends itself to use in various forms of installations. The water cylinder may serve only one ejector tube or it may serve a number of ejector tubes arranged in battery, such as illustrated, in Figs. land 2, or the battery arrangement may be one such as diagrammatically illustrated in Fig. 2A. In the installation indicated in Fig. 2A three ejector tubes 10 (e, f, g) arranged in vertical alignment may be served by Water cylinder 11a and plenum chamber 24e, while a similar battery of ejector tubes 10 (h, i, j) may be served by water cylinder 11h and plenum chamber Mb. The disclosure will suggest other arrangements for installations embodying the invention.

From the foregoing description it will be seen that the invention provides many advantages. The arrangement of the porting of the water cylinder and the piston traversing the ports permits the energy built up in the moving mass of water flowing behind the piston in its forward stroke to be utilized in providing additional flow of water into the ejector tube even after the water piston has come to a standstill. The utilization of this energy to pump water obviates the need for absorbing or dissipation of that energy within the structure. Thus, a shorter stopping distance for the water piston and reduction of ducts, than otherwise would be the case, is made possible.

Also a shorter working stroke of the water piston is made possible than otherwise would be the case, since the flow of water, after the piston has come to astandstill in its forward or driving stroke, assists in the expulsion of the torpedo from the ejector tube.

The arrangement of the water cylinder suction and discharge, being hydraulically balanced with submergence or ambient pressure of the sea permits the expulsion of missiles at any ambient or submergence pressure without changing the energy requirement for the expulsion of the missiles, as is the case when an unbalanced system is used. In an installation embodying the invention, the energy expended in expelling the missile from an ejector tube is only the energy required to accelerate and move 1 1 the respective masses of water and the missile. These as well as other advantages result from utilization of the invention.

The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalent of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed.

What is claimed is:

1. In a balanced system for ejecting missiles from an installation on a submarine or from other similar installations submerged under the surface of the sea, a missile ejecting tube whose muzzle end is submerged below the surface of the sea, a water cylinder, a passageway connecting said cylinder with the sea whereby the hydraulic pressure from the sea is substantially the same in said water cylinder as it is at said muzzle end, means defining a conduit connecting said water cylinder and said ejection tube for the passage of water from said cylinder into said tube, a piston and rod mounted for reciprocation in said water cylinder, which piston on its stroke from retracted position forces water ahead of it from said cylinder into said tube for ejecting a missile therefrom while drawing water behind it into said cylinder through said passageway, means for reciprocating said piston, means including water ports in said cylinder cooperating with said piston to provide escape from said cylinder into said tube for water moving behind the piston whereby the energy built up in the mass of water moving behind the piston is dissipated through said tube when said piston is brought to rest at the end of its stroke from retracted position.

2. Apparatus constructed according to claim 1 in which the ports in the water cylinder are elongate and tapered in shape and circumferentially spaced around the cylinder and located near the fore end of said cylinder and enclosed by a housing which provides the conduit connecting the Water cylinder and ejection tube and in which said water cylinder ports are traversed by said piston near the end of its forward stroke and the piston sltirt length is less than the length of said water cylinder ports whereby the efiective outlet area of said ports ahead of the face of said piston is progressively decreased and outlet area of the ports behind the back of the piston provides progressively increased escape area for water moving forward behind said piston as the piston in its forward stroke is traversing said Water cylinder ports.

3: Apparatus constructed in accordance with claim 1 in which said tube is provided with a part having an openable and closeable valve for permitting or preventing flow of water through said conduit into or from said tube.

4. Apparatus constructed in accordance with claim 3, in which the means for reciprocating the piston in the water cylinder is another piston reciprocatable in a compressed air cylinder and in which the piston in the air cylinder is connected to the rod of the piston in the water cylinder and the piston in the air cylinder is driven by compressed air.

5. Apparatus constructed in accordance with claim 4, in which the piston in the air cylinder is operated in response to actuation of a firing valve which valve is actuated by a compressed fluid such as compressed air or the like.

6. Apparatus constructed according to claim 1, in which the end wall closing the forward end of the water cylinder is provided with an inwardly extending bumper stop having a resilient elastomer member against which a bumper member on the piston in the water cylinder strikes at the end of itsforward stroke.

7. Apparatus constructed according to claim 6 in which a dash pot piston connected to the piston rod of the water cylinder piston engages a dash pot when said water cylinder piston is returned to retracted position after a forward stroke.

8. Apparatus constructed according to claim 1 in which a single water cylinder is connected to serve two or more ejection tubes arranged in a battery.

9. Apparatus constructed according to claim 8 in which the ejection tubes in the battery extend through a housing which provides a single plenum chamber connecting each of the ejection tubes of the battery with the water ports of the single water cylinder and each of the ejection tubes in the battery is provided with independently openable and closeable ports located within said housing.

References Qited inthe file of this patent UNITED STATES PATENTS 387,517 Jackson Aug. 7, 1883 425,574 Lassoe Apr. 15, 1890 441,676 Lovegrove Dec. 2, 1890 708,552 Holland Sept. 9, 1902 2,445,326 Janney July 20, 1948 FOREIGN PATENTS 133,432 Great Britain Oct. 8, 1919 349,674 Italy June 13, 1937 

